How severe is CVE-2020-12140?

CVE-2020-12140 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-12140 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-12140?

CVE-2020-12140 affects Contiki-ng. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-12140?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-12140 published?

CVE-2020-12140 was published on 2021-12-07 and last updated on 2026-06-17.

CVE-2020-12140

CVE-2020-12140 is a high-severity vulnerability in Contiki-ng with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-120.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 8.3
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Contiki-ng
Published: 2021-12-07
Last modified: 2026-06-17

Description

A buffer overflow in os/net/mac/ble/ble-l2cap.c in the BLE stack in Contiki-NG 4.4 and earlier allows an attacker to execute arbitrary code via malicious L2CAP frames.

Frequently asked questions

What is CVE-2020-12140?: A buffer overflow in os/net/mac/ble/ble-l2cap.c in the BLE stack in Contiki-NG 4.4 and earlier allows an attacker to execute arbitrary code via malicious L2CAP frames.
How severe is CVE-2020-12140?: CVE-2020-12140 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-12140 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-12140?: CVE-2020-12140 affects Contiki-ng. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-12140?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-12140 published?: CVE-2020-12140 was published on 2021-12-07 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:contiki-ng:contiki-ng:*:*:*:*:*:*:*:*

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